There are grooves inside the pump where the relief spring plunger goes; cell phone camera didn't quite capture the image I wanted. When I first started this process to rotate engine, plugs were pulled and carb blocked @ WoT, but still tough to turn. This was the first filter. What I mean by that is oil pan full of gas, so I did an oil change with fresh filter (I use WIX 51515).
New pump for sure. What I'm gonna do is this. The Rodeo is in town, and as usual, they brought the cold, rainy weather with them. Will be warm and sunny next week. I'm persuaded to pull the oil pan, and as recommended, check crank and rods for looseness, check the oil pick-up tube. When engine rebuilt in '97, I had machinist modify block to use a hemi 1/2" pick-up tube. I'm using a windage tray. Don't know if this is useful info.
Right now, pessimistically, I think I'm looking at a short block rebuild. But, you guys have given me areas to work on that I did not realize that show some hope.
If all is well with crank, rods, and pick-up, as recommended, I'll put engine together and see what happens.
Alrighty, well the fun begins on Monday. Enjoy your weekend.